In the operation of an electrical load it may be useful to detect an electrical hazard condition, such as a short circuit or overvoltage condition. For example, an electrical load may include two input terminals, and may be driven by applying a voltage or current between these input terminals. In case of a failure, a short circuit condition may occur between the input terminals, such that the electrical resistance provided by the load between the input terminals drops drastically. This can potentially lead to a hazardous situation due to greatly increased current flow, such as overheating.
In particular, hazard detection may be useful for LED lighting elements, quite specifically for organic light emitting diode elements (OLED).
EP 2 456 057 A2, for example, discloses a power converter supplying a driving voltage for the operation of an organic light emitting display device. The power converter includes a voltage conversation unit that provides a first and second driving voltage at a first and second output electrodes. A short detection unit generates a control signal by comparing, during a short detection period, a magnitude of a voltage of the second output electrode to a magnitude of a reference voltage. In response to the control signal, the power converter is configured to shut down, such that when a magnitude of the voltage of the second output electrode is equal to or larger than the magnitude of the reference voltage during the short detection period no further driving voltage is applied.